Employing Rapid Prototyping to Assist Free Fibular Flap Reconstructive Surgery of Mandibular Defects

Abstract:

Patients suffering from mandible tumors often require a reconstructive surgery to repair the defects caused by large tumors. The particular type of reconstructive surgery studied in this paper is called free fibular flap reconstruction, which uses fibular segments to replace removed sections of the mandible and a titanium plate to provide strength. In order to decrease the dependence on design experience, decrease surgery time, and enhance the participation of surgeons in the design process, Rapid Prototyping (RP) biomedical models were employed to enable good visualization of the original and reconstructed geometry and for use as forming guides for the customized titanium plates. This study reports on one male and one female patients who underwent mandibular reconstruction. In one case, the operation time was reduced 2 hours and the other one was reduced 1.8 hours. The customized titanium plate shapes conformed to the patients’ mandible anatomy and were thick enough to provide the strength and stiffness needed to fix the mandible until the bone grafts and soft tissues heal.

• Periodical: Key Engineering Materials (Volumes 467-469)
• Pages: 1633-1638
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.467-469.1633
• Online since: February 2011
• Authors: Wen Zheng Wu, Xing Jun Qin, David W. Rosen, Ya Dong Chen, Wan Shan Wang
• Keywords: Biomedical Engineering, Computer Aided Design (CAD), Mandible Reconstruction, Prosthetics, Rapid Prototyping (RP), Rehabilitation Engineering

References

[2] 3 RP model manufacturing. In this study, the mandible RP model was fabricated by an Objet Eden 250 system. The STL files output from Magics were input into the Objet Studio software to set up the builds. The fabrication time of reconstructed mandible RP model for Case 1 was 9 hours 18 minutes and Case 2 was 9 hours 54 minutes.

[2] 4 Manufacturing customized titanium plate. The conventional design process of titanium plate is prior to surgical interventions. The efficiency and accuracy of the conventional method is mainly dependent on experiences and skills of the designer. In order to decrease the dependence on design experience and enhance the participation of surgeons in the design process, designing and fabricating a customized titanium plate implant should be employed. Titanium has good properties for medical applications, such as excellent biocompatibility, specific strength, low density, and good corrosion and oxidation resistance. A custom fabricated titanium plate, and titanium nails, was employed in the fixation of reconstructed mandible. The RP model of reconstructed mandible, Figure 3, was used as a pattern when the titanium plate was formed. In this manner, the surgeons can assure a good fit between the plate and the patient's mandible before surgery by test-fitting the plate to the mandible model. The customized titanium plate is shown in Figure 3. Figure 3 Customized titanium plate and reconstruction mandible RP model.

[2] 5 Reconstructive surgery of madibular defects. After the titanium plate was formed it could be take into in operation room for the reconstructive surgery using. The doctor cut a approximately 70 mm tumor from the case 1 patinet's mandible as shown in Figure 4. The doctor also needed to cut the patient's fibular as a requirment according to the mandible defect size (Figure 5). Figure 4 The removal part of patient Figure 5 The cut fibular After the resection of the mandible tumor and fibular, the doctor could reconstruct the mandible using the fibular sections. The reconstructive mandible after fixing by the customized titanium plate and titanium nails was shown in Figure 6. Figure 6 The reconstruction mandible.

DOI: 10.1097/prs.0b013e3181c72625

[3] Results Through the doctors' clinical inspecting and comparing a lot of cases, the customized titanium plate design achieves a good balance between mechanical and biological considerations. The titanium plate shape conforms to the patient's mandible anatomy and is thick enough to provide the strength and stiffness needed to fix the mandible until the bone grafts and soft tissues heal.